Mercury May Have Once Had An Ocean Of Lava

Alex Knapp, Forbes Staff

Researchers at MIT have recently published an experiment that demonstrates that 4 billion years ago, the planet Mercury may have had an ocean of magma on its surface.

The study began as the scientists were studying data from NASA’s Messenger probe about the composition of Mercury’s surface. In studying the data from the probe, the scientists were puzzled by two radically different rock compositions. That led them to try to determine what type of geological process would result in those rocks.

To figure it out, the researchers used the Messenger data to reconstruct the two different kinds of rocks. They then subjected those rocks to different temperatures and pressures to simulate different processes that may have occurred on Mercury’s surface. In the end, the only explanation that fit the data was that Mercury at one time had an ocean of magma on its surface. And a long time ago, at that.

“The thing that’s really amazing on Mercury is, this didn’t happen yesterday,” said MIT geologist Timothy Grove in a press release. “The crust is probably more than 4 billion years old, so this magma ocean is a really ancient feature.” ...